Hi welcome to JA.com.I will answer your question the best I can,
The switches are susceptible to water damage, and new revised switches are available to prevent this problem.
This is why on a lot of Mitsubishi, the green or yellow light flash when not selectedTSB
4WD INDICATOR LAMP FLASHING/DTC 33 TECHNICAL SERVICE BULLETIN
Reference Number(s): TSB-02-23-007
, Date of Issue: November 2002 PURPOSE
Due to moisture entry, the transfer shift position switch terminals may corrode, causing the 4WD indicator lamp to begin flashing and/or Diagnostic Trouble Code 33 to set.
To eliminate this condition, replace the transfer switches with the new, improved switches listed in this bulletin.
Vehicles produced since 2/26/01 have transfer switches with corrosive-resistant terminals. AFFECTED VEHICLES 2001-2002 Montero vehicles produced before 2/26/01 PROCEDURE 1.
Replace the five transfer switches indicated below, using the improved parts listed in the PARTS INFORMATION section of this bulletin.
Refer to Group 23 of the appropriate service manual. Fig.
1:Transfer Switch Locations
2. Clear the DTC, using the scan tool.
3. Test drive the vehicle to confirm the 4WD indicator lamp does not flash and DTC 33 does not reset.
MITSUBISHI: 2001-2002 Montero GROUP: 23 Automatic Transmission
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